1. Field of the Invention
The present invention relates generally to catheter devices which are inserted into a body cavity, duct, or vessel of a human or animal patient to allow drainage, administration of fluids or gases, or access by surgical instruments. More particularly, it relates to catheters which are inserted and positioned in patients for longer time frames such as periphery inserted central catheters (PICC or PICC line) and to a PICC line which enhances bio compatibility through a titanium exterior surface.
2. Prior Art
Catheters have been employed in medicine since the late 19th century and disposable catheters have been used widely since the mid 20th century. Modern disposable catheters are constructed from a range of polymeric materials including polyethylene, polyurethene, silicone rubber, latex, and thermoplastic elastomers. Silicone is one of the most common choices because it is considered substantially inert and unreactive to body fluids and a range of medical fluids with which a catheter may come into contact.
Conventionally, modern disposable catheters are made from polyurethane and are provided by manufacturers in different lengths and sizes for men, women, children and animals. The most advanced catheters have a thin surface coating (hydrophilic coating). When immersed in water or a water bearing fluid, this hydrophilic coating swells to a smooth, slippery film making the catheter safer and more comfortable to insert.
PICC lines are an intravenous form of a catheter used in the medical field. Such PICC lines are often left implanted in a patient for consecutive uses for prolonged periods of medical treatment. Examples of a long term venous engagement of PICC lines includes chemotherapy and extended antibiotic therapy, to name a few.
In use, generally speaking, the PICC line is inserted in a peripheral vein, most commonly in the upper arm of the patient, and extends to the terminating end near large blood vessels in the chest of the patient, proximate to their heart. Such positioning of the distal end of the catheter provides a long term intravenous access for placing medicine in the blood stream near the heart. The catheter, being typically a slender flexible tube generally also employs a guide wire to aid in inserting and positioning the distal end of the catheter in the patient's body and is commonly known in the art.
After such insertion, the catheter employed as a PICC line is conventionally left engaged in the blood vessels of the patient for periods of weeks or months. While engaged with patient in this as-used position, when not in use, the PICC line can be flushed out and capped off. When medicine is to be communicated to the patient's bloodstream, communication is provided through the axial passage of the PICC line exiting at the distal end near the heart.
Because PICC lines and other forms of catheters remain in an engagement with a patient's body, potentially for long time periods, cleanliness and bio-compatibility of the engaged catheter are highly important and infection can be a continuing problem for a patient. When bio-compatibility is an issue, the patient's vein may become infected or irritated by the line, often referred to as mechanical phlebitis. Further, fibrin or other encapsulate may adhere to the catheter causing further complications.
Bio-compatibility of catheters is often dictated by the catheter material or coating thereof. Current conventional catheters employ silicone, polyvinyl chloride, or latex rubber tubing which may have an exterior with a silver, hydrogel, or silicone coating. However, these materials incur some problems with breakage, waste disposal after use, blood clot formation, infection, and allergy concerns.
As such there exists an unmet need for an improved catheter with enhanced bio-compatibility for employment where such a catheter is anticipated to be engaged with a patient for long time periods of weeks or months. Additionally, such a catheter having such improved bio-compatibility would be a benefit for patients who are especially sensitive to catheter insertion even for short periods of time.
Such an improvement should be easily employed with existing catheter designs and the installed base of such medical catheters to allow for easy and widespread distribution to help patients immediately. Such an improvement should also be employable at a reasonable cost to thereby allow for low-cost bio-compatible catheters to thereby ensure widespread distribution and use and to thereby provide improved medical services to the largest number of patients.